Cannabis reduces some of the pain and nausea from chemotherapy and stimulates appetite.
One of the most well-known medical uses of marijuana is for people going through chemotherapy. There's good evidence that it's effective for this, according to the National Academies report.
Cancer patients being treated with chemo suffer from painful nausea, vomiting, and loss of appetite. This can cause additional health complications.
Marijuana can help reduce these side effects, alleviating pain, decreasing nausea, and stimulating the appetite. There are also multiple FDA-approved cannabinoid drugs that use THC, the main active chemical in marijuana, for the same purpose.
Marijuana can help people who are trying to cut back on drinking.
Marijuana is safer than alcohol. That's not to say it's risk-free, but cannabis is much less addictive than alcohol and doesn't cause nearly as much physical damage.
Disorders like alcoholism involve disruptions in the endocannabinoid system. Because of that, some people think cannabis might help patients struggling with those disorders.
Research published in the Harm Reduction Journal found that some people use marijuana as a less harmful substitute for alcohol, prescription drugs, and other illegal drugs. Some of the most common reasons patients make that substitution are that marijuana has less negative side effects and is less likely to cause withdrawal problems.
Some people do become psychologically dependent on marijuana, and it is not a cure for substance abuse problems. But from a harm-reduction standpoint, it can help.
Still, it's worth noting that combining marijuana and alcohol can be dangerous, and some researchers are concerned that this scenario is more likely than one in which users substitute a toke for a drink.
Medical marijuana legalization seems to reduce opioid overdose deaths.
While there are a number of factors behind the current opioid epidemic, many experts agree that the use of opioid painkillers to treat chronic pain has played a major role. It's very risky to take powerful drugs that have a high risk of causing overdose and high addiction rates. Marijuana, which can also treat chronic pain, is far less risky.
Several studies have shown that states that allow medical marijuana have fewer opioid deaths. This effect seems to grow over time, with states who pass these laws seeing a "20% lower rate of opioid deaths in the laws' first year, 24% in the third, and 33% in the sixth," according to Stat News.
It's hard to say that deaths went down because of medical marijuana legalization and not other reasons. But because the effect seems to get stronger the longer marijuana remains legal, researchers think marijuana is a likely cause of the decline in opioid deaths.
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